:root {
    --primary: #1a73e8;
    /* Default, will be overridden by header */
    --secondary: #ff5722;
    /* Default, will be overridden by header */
    --text-main: #2d3748;
    --text-muted: #718096;
    --bg-light: #f7fafc;
    --white: #ffffff;
    --border: #e2e8f0;
    --shadow: 0 4px 6px rgba(0, 0, 0, 0.05);
    --radius: 12px;
    --container: 1200px;
}

* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
    font-family: 'Inter', sans-serif;
}

body {
    background-color: var(--bg-light);
    color: var(--text-main);
    line-height: 1.6;
}

a {
    text-decoration: none;
    color: inherit;
    transition: 0.3s;
}

.container {
    max-width: var(--container);
    margin: 0 auto;
    padding: 0 1.5rem;
}

/* Header */
header {
    background: var(--white);
    box-shadow: var(--shadow);
    padding: 1rem 0;
    position: sticky;
    top: 0;
    z-index: 1000;
}

.nav-wrapper {
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.logo img {
    max-height: 50px;
}

.logo span {
    font-size: 1.5rem;
    font-weight: 700;
    color: var(--primary);
}

.nav-menu {
    display: flex;
    gap: 2rem;
    align-items: center;
}

.nav-link {
    font-weight: 500;
    font-size: 0.95rem;
}

.nav-link:hover {
    color: var(--primary);
}

.search-box {
    position: relative;
    width: 250px;
}

.search-box input {
    width: 100%;
    padding: 0.6rem 1rem 0.6rem 2.5rem;
    border: 1px solid var(--border);
    border-radius: 20px;
    outline: none;
    font-size: 0.9rem;
}

.search-box i {
    position: absolute;
    left: 1rem;
    top: 50%;
    transform: translateY(-50%);
    color: var(--text-muted);
}

/* Hero Section */
.hero {
    background: linear-gradient(135deg, var(--primary) 0%, #3182ce 100%);
    color: white;
    padding: 5rem 0;
    text-align: center;
    border-radius: 0 0 50px 50px;
}

.hero h1 {
    font-size: 3rem;
    margin-bottom: 1.5rem;
    font-weight: 800;
}

.hero p {
    font-size: 1.2rem;
    opacity: 0.9;
    max-width: 700px;
    margin: 0 auto 2.5rem;
}

/* Featured & Grids */
.section-title {
    margin: 4rem 0 2rem;
    display: flex;
    justify-content: space-between;
    align-items: flex-end;
}

.section-title h2 {
    font-size: 1.75rem;
    font-weight: 700;
}

.resource-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
    gap: 2rem;
}

.resource-card {
    background: var(--white);
    border-radius: var(--radius);
    overflow: hidden;
    box-shadow: var(--shadow);
    transition: transform 0.3s;
    border: 1px solid var(--border);
}

.resource-card:hover {
    transform: translateY(-5px);
}

.card-img {
    height: 180px;
    overflow: hidden;
}

.card-img img {
    width: 100%;
    height: 100%;
    object-fit: cover;
}

.card-content {
    padding: 1.5rem;
}

.card-cat {
    font-size: 0.75rem;
    text-transform: uppercase;
    font-weight: 700;
    color: var(--primary);
    margin-bottom: 0.5rem;
}

.card-title {
    font-size: 1.1rem;
    font-weight: 700;
    margin-bottom: 0.75rem;
    display: block;
}

.card-footer {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding-top: 1rem;
    border-top: 1px solid var(--border);
    font-size: 0.85rem;
    color: var(--text-muted);
}

/* Footer */
footer {
    background: #1a202c;
    color: white;
    padding: 4rem 0 2rem;
    margin-top: 5rem;
}

.footer-grid {
    display: grid;
    grid-template-columns: 2fr 1fr 1fr;
    gap: 4rem;
    margin-bottom: 3rem;
}

.footer-col h3 {
    font-size: 1.25rem;
    margin-bottom: 1.5rem;
}

.footer-links {
    list-style: none;
}

.footer-links li {
    margin-bottom: 0.75rem;
}

.footer-links a:hover {
    color: var(--primary);
}

.footer-bottom {
    text-align: center;
    padding-top: 2rem;
    border-top: 1px solid rgba(255, 255, 255, 0.1);
    font-size: 0.9rem;
    color: #a0aec0;
}

/* Responsive */
@media (max-width: 768px) {
    .nav-menu {
        display: none;
    }

    .hero h1 {
        font-size: 2rem;
    }

    .footer-grid {
        grid-template-columns: 1fr;
        gap: 2rem;
    }
}

/* Ad Placements */
.ad-header {
    text-align: center;
    margin: 1rem 0;
}

.ad-footer {
    text-align: center;
    margin: 3rem 0;
}

.ad-sidebar {
    margin-top: 2rem;
}